(For a Reuters live blog on U.S., UK and European stock markets, click LIVE/ or type LIVE/ in a news window) * FTSE 100 up 0.5%, FTSE 250 adds 0.3% Dec 10 (Reuters) - London’s exporter-heavy FTSE 100 edged higher on Thursday as the absence of a Brexit trade deal pressured the pound, while concerns around the economic damage from the COVID-19 pandemic kept the mid-cap index subdued. The FTSE 100 was up 0.5% by 0802 GMT, led by consumer staples, materials and energy stocks. Prime Minister Boris Johnson and the European Union’s chief executive gave themselves until the end of the weekend to seal a new trade pact after failing to overcome persistent rifts over dinner on Wednesday. The mid-cap index rose just 0.3%, as data showed Britain’s economic recovery almost ground to a halt in October due to a surge in coronavirus cases. In company news, Mike Ashley’s British sportswear group Frasers jumped 6.5% to the top of the FTSE 250 after reporting a 25% rise in first-half core earnings. (Reporting by Sagarika Jaisinghani in Bengaluru; Editing by Arun Koyyur)